Crafty Russian operatives gave goodie bags to world powers at the G-20 summit with USB drives and phone chargers — but they were “Trojan Horses” designed to download info and send it back to the motherland.

The cloak-and-dagger spy game played out at last month’s conference in St. Petersburg, where Vladimir Putin and President Obama appeared to patch up their feud.

But little did Obama know that Putin’s henchmen were making sure every delegate at the G-20 walked out with equipment that could compromise state secrets.

The clever Boris-and-Natasha ploy was reported Tuesday by the major Italian newspapers La Stampa and Corriere della Sera as the US remains under fire for NSA spying on world leaders’ phone calls.

European Union President Herman Van Rompuy became suspicious of the gift-bag devices, which bore the red-and-blue “Russia G20” logo, so he asked technical experts in Belgium and Germany to check them out, according to EU sources.

German intelligence determined the three-pronged mobile-phone chargers could tap into e-mails, text messages and phone calls and, like the USB thumb drives, were a “poisoned gift” from summit host Putin, La Stampa said.

Italian media — which have been expressing outrage for months over alleged NSA excesses — reported Tuesday that a warning went out to all G-20 members about the dangerous gifts.

The two newspapers said all “delegates” at the Sept. 5-6 gathering were given the goodie bags. It wasn’t clear if any world leaders received the tainted gifts directly.

Putin’s spokesman denied the allegations.

“It is definitely nothing other than an attempt to switch attention from the problems that really exist,” Dmitry Peskov said.

Ironically, the G-20 summit was hailed as a breakthrough conference where Obama and Putin were said to have smoothed over the bitterness that had just intensified when the Kremlin granted NSA leaker Edward Snowden asylum in Russia.

The latest incident recalled the “Trojan Horse” scandal of the early Cold War, when Soviet schoolchildren presented a wooden replica of the Great Seal of the United States to the US ambassador to Russia. The seal hung in the ambassador’s residential office for six years before US officials found it contained an eavesdropping bug.

Earlier this year, the Kremlin expressed outrage over reports that Britain had spied on delegates at two previous G-20 summits via compromised Internet cafes and by hacking into BlackBerrys.